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A076959
Number of primes between 3^n and 4^n.
2
0, 2, 9, 32, 119, 435, 1573, 5695, 20773, 76057, 279850, 1033937, 3837070, 14296494, 53468768, 200673056, 755606952, 2853697709, 10807617884, 41036410818, 156186010430, 595759180892, 2277112205791, 8720036044777, 33451314673521, 128533154571957
OFFSET
1,2
LINKS
FORMULA
a(n) = A086680(n) - A055729(n).
PROG
(PARI) a(n) = primepi(4^n) - primepi(3^n); \\ Michel Marcus, Mar 22 2015
CROSSREFS
Sequence in context: A077644 A292482 A053369 * A003697 A006253 A045630
KEYWORD
nonn
AUTHOR
Amarnath Murthy, Oct 21 2002
EXTENSIONS
More terms from Ralf Stephan, Oct 31 2002
a(14)-a(26) added by David Baugh, Mar 22 2015
STATUS
approved